Final answer:
During middle adulthood, men undergo a reduction in the production of the hormone testosterone, known as andropause or male menopause. This can result in various symptoms and changes in the male body.
Step-by-step explanation:
During middle adulthood, men undergo a reduction in the production of the hormone testosterone, known as andropause or male menopause. This is a natural process that occurs as men age. It can result in symptoms such as fatigue, reduced muscle mass, depression, anxiety, loss of libido, and sexual dysfunction. However, testosterone levels decline gradually and rarely affect sperm production until very old age.